I just searched on the internet and found that there are no direct flights between these two cities. Thus, you are suggested to take a flight from Kashgar to Urumqi, then take flight from Urumqi to Shanghai and reach Ningbo by taking train or bus.

Here is the flight schedule for your reference:
Kashgar- Urumqi HU7748 1040/1225
Urumqi-Shanghai Hongqiao MU5634 1835/2250